In the current image and video coding standards, such as MPEG-1, MPEG-2, MPEG-4, H.261, H.263, and JPEG, quantized DCT coefficients are entropy coded using a so-called run-value coding technique. A. problem with this ...
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ISBN:
(纸本)0819431249
In the current image and video coding standards, such as MPEG-1, MPEG-2, MPEG-4, H.261, H.263, and JPEG, quantized DCT coefficients are entropy coded using a so-called run-value coding technique. A. problem with this technique is that the statistics of the run-value symbols are highly dependent on the quantization step size and the dynamic range of the DCT coefficients. Therefore, a single fixed entropy coding table cannot achieve the optimal coding efficiency for all possible quantization step sizes and all possible dynamic ranges of the DCT coefficients. bitplane coding of the DCT coefficients is a new coding scheme that overcomes this problem. It provides a better performance than run-value coding under all conditions.
We propose anew simple image coder based on Discrete Wavelet Transform (DWT). The DWT coefficients are coded in bitplanes. We use a variable order Markovian model to code the DWT coefficient bitplanes. Recently, we ha...
详细信息
ISBN:
(纸本)0819424331
We propose anew simple image coder based on Discrete Wavelet Transform (DWT). The DWT coefficients are coded in bitplanes. We use a variable order Markovian model to code the DWT coefficient bitplanes. Recently, we have developed this method that used 65 contexts(7). In this paper, the number of contexts is reduced to 34. We show the experimental results, both in terms of distortion measurement and visual comparison, and compare them to well-known methods.
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